Regular readers may recall my previous assertion that quality improves steeply at first but rises slowly beyond around the £20 mark.

At that price some outstanding wines are available that could comfortably challenge £100 bottles for taste and hammer them in terms of value.

However the notions of value and bargain are related to what drinkers are willing to pay and personal taste.

With this in mind, today I’m comparing two reds and two whites, all on offer at Asda and all from similar grapes, but in different price bands.

A couple of months ago I reviewed some ever-reliable Wolf Blass Yellow Label whites and reds. Yellow Label is one of the South Australian producer’s everyday drinking brands, but the wines were pretty decent and good value at the special price of £5 that a number of supermarkets were offering at the time.

Asda is currently selling Wolf Blass Red Label shiraz cabernet (red) and chardonnay semillon (white) reduced to £5.98 until August 15. Higher up the range, Asda is also selling Wold Blass Silver Label shiraz cabernet and chardonnay reduced from £12.99 to £9. Now this isn’t cheap but it does represent a big reduction on what is by reputation a high-quality wine. So how good is it?

The shiraz cabernet 2008 has a delicious, powerful nose – generally lacking in lesser quality wines and therefore a good sign. To taste it displays concentrated ripe fruit with fine tannins, vanilla, spice and blackberry. Thumbs (and bottoms) up for this one.

On to the Silver Label chardonnay 2009; a good nose and a concentrated, deep flavour of lemon, peach and apricot. Cream is evident early on giving way to a crisp long finish. Of the two, the shiraz cabernet won the nose but the chardonnay took the honours with its excellent taste.

So on to a cheaper tipple. South Africa’s Millstone private vineyard range is reduced by £3 at Asda to £4.98 until August 15.

There’s a taste in many South African reds that I can’t quite describe other than to say it’s unmistakably South African. Millstone’s cabernet 2010, made by FirstCape in the Western Cape, displays a ‘soggy’ unremarkable nose with inky, plum flavours and that South African taste. It’s ok but a little rough at the edges.

The Millstone Chardonnay 2009, is significantly better. With smoky oak at the fore, this white is reasonably balanced and smooth. There’s nothing to rave about but if you’re into big, brash, new world-style chardonnays then this may be for you.

So the verdict. Pay more or go for cheap but in this case not so cheerful? If you’ve got the cash, go for the Wolf Blass which is less than double the price but far more than double the pleasure.

Fact of the Week: FirstCape was created in 2002 as a UK and South African joint venture to allow farmers and growers to supply the UK market. It started with the De-Wet Co-operative and 38 growers. Today it has five Co-operative shareholders and more than 200 farms grow for the brand.